This invention relates generally to electronic sensors for sensing the direction of a resultant force vector of the gravity and inertial forces, and more particularly concerns audible electronic indicators for assisting pilot coordination of aircraft controls. Presently, aircraft coordination indicators are visual and give poor feedback to a pilot inasmuch as the pilot must direct his visual attention outside of the aircraft in maneuvers near the ground. As a result, poor coordination of the aircraft controls has become a serious problem and too often has resulted in stall/spin accidents. When aircraft controls are perfectly coordinated a stall may be executed without either wing dropping and without the plane entering a spin. Accordingly, the need has developed for a coordination indicator which frees the pilot from watching an instrument in the cockpit.